<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        /*//CSS样式*/
        div {
            text-align:center;
            border:2px solid #a1a1a1;
            padding:10px 40px;
            background:#dddddd;
            width:350px;
            border-radius:25px;
        }
    </style>
</head>
<body>
<div>CSS3新属性允许向元素添加圆角</div>
</body>
</html>
